Dropping below the current 19 ships even for a short time would be "completely unacceptable" and leave the UK lacking the maritime strength to deal with the threats it faces from areas like Russia, the Defence Select Committee said.

And the Labour peer agreed that the nation's capabilities had been "suffering death by a thousand cuts".

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Arguing that the Government must now review the size of the armed forces to keep them competitive in an increasingly dangerous world, Lord West listed six conflicts that could scupper our diminutive fleet.

War with Russia, conflict in the Falklands and spiralling tensions in the Middle East could prove too challenging for our maritime capabilities, he said.

Lord West said while war with Argentina was unlikely, a battle in the South Atlantic could stretch the Royal Navy to breaking point.

He said the UK did not have enough frigates, destroyers and aircraft carriers to deploy to the Falklands if another conflict elsewhere in the world also flared up.

Royal Navy photo competition winners 2016

Tue, June 7, 2016

Breathtaking images issued by the Ministry of Defence of the Peregrine Trophy awards 2016
Will Haigh won Royal Navy Photographer of the Year 2016
Simmo Simpson won Best Maritime Image Award
Jamie Weller won Royal Navy Amateur Maritime Image Award
Joel Rouse won People's Choice Award

Commenting on tensions with Russia, the retired military chief said the UK has too few nuclear attack submarines and was still awaiting delivery of two aircraft carriers, which will not be operational until 2020.

On tensions in the Mediterranean, the former First Sea Lord said Britain could easily be drawn into a war in the region if Turkey - a NATO member - was attacked.

That conflict would almost certainly involve a large sea component, requiring the Royal Navy to commit assets to the fight.

Likewise, the wars in Syria and Iraq and the increasingly likelihood of fresh tensions with Iran could see our maritime fleet called upon in the Gulf.

In Asia, fears over the nuclear missile programme in North Korea and tension in the South China Sea may in the future require Britain to deploy warships, either in a peacekeeping or offensive capacity.

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A battle in the South Atlantic could stretch the Royal Navy to breaking point, he said

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MPs said they had "serious concerns" about the funding and timetable of the new fleet

Writing in The Sun, he said: "The Navy has historically provided global stability — but in my 51 years of service I have never known such a chaotic world as the one we live in today.

"There are a number of tasks we have fulfilled over the years that have helped to keep security and stopped wars. We are now not even fulfilling those.

"I am particularly worried about Russia. Putin is talking about nuclear options, they are carrying out cyber attacks, taking down a French TV station, fighting in the Ukraine and threatening the Baltics.

"Then you look in the Far East and you have China saying that the whole of the South China Sea is theirs."

Meanwhile, a former military chief has warned that Britain's defence plans are "not fit for purpose".

Lord Boyce, an independent cross-bencher who served as chief of the defence staff from 2001 to 2003, said the UK's forces were "shrinking" in the face of a resurgent Russia.

He said: "Brexit is surely going to demand that we are prepared to operate more autonomously.

"Surely the Government must realise that SDSR '15 is not fit for purpose."

But Defence minister Earl Howe responded: "We are satisfied that the armed forces will be the right size to meet our defence and security policy requirements.

"I say that without wishing to give the impression that we are complacent, because we are not.